How clean is your water bottle? A CBS4 Problem Solvers investigation

INDIANAPOLIS, Ind. – Reusable water bottles are breeding grounds for bacteria.

CBS4 swabbed three Hoosiers’ water bottles and one dirty dog dish. We sent the samples to Hoosier Microbiological Laboratory in Muncie for testing.

“That’s pretty nasty,” Jaima Ballentine, the lab’s manager admitted. “The dog dish was much cleaner.”

First up, our crew met up with a runner along the Monon Trail. John Hauber said he likes his water bottle because it’s easy to hold on to.

“I don’t wash it because I’m the only one using it and I figure if it has germs, it’s just mine,” he said.

Hauber said he washes his water bottle every third or fourth use. It showed. His test results turned up fairly clean, compared to the others.

HML’s baseline, or minimum detection level, is five colony-forming units per swab. They harvest the bacteria for 24 hours and allow it to form into colonies so that they can better detect the germs.

Hauber’s samples showed fairly clean results. His water bottle showed 50 CFUs per swab.

Next up, a CrossFit athlete who rarely washes his stainless-steel water bottle. Doug Halman admitted he washes it every month or two in the dishwasher. His sample results were downright disgusting, turning up more than 100,000 CFUs per swab.

“We couldn’t even count that,” Ballentine said. “It was so full of bacteria.”

Halman agreed with the runner.

“I figure it’s just my germs so it’s just kind of a recycling effect,” he laughed. “It keeps me healthy. It’s my own microbes coming back.”

Last but not least, we wanted to test one of our news director’s water bottles. She is known to keep several in her office at a time. Yet, she rarely washes them.

“All I do is drink water,” Kerri Cavanaugh said. “I’m constantly filling up my bottle and I’ll rinse it out but we’re in the news business and sometimes it’s hard to take a half second to rinse it out.”

Cavanaugh is always running around. Her test results showed 5,750 CFUs per swab; not the worst, but certainly not clean.

“It’s not a good feeling! But you know, that’s why we’re doing this story,” Cavanaugh said.

When compared to the dog dish, two out of the three water bottles we tested were dirtier. The dog dish turned up 700 CFUs per swab.

“I would rather drink out of the dog dish than that water bottle," Ballentine said. “To put in perspective, a pool sample, when we test those, they’re allowed 200 CFUs.”

Cavanaugh said she will wash her water bottles more often now.

Doctors encourage everyone to wash their reusable water bottles with soap and hot water after every use. While a person’s stomach acid will kill most of the bacteria that one eats or drinks, it only takes a tiny organism in order to get sick.

Studies done in the past show straw tops are the easiest to clean and that water bottles with slide tops typically collect the most bacteria.